Hi Adam, as a first check, you should ensure your imsmanifest.xml file is pointing to index.html, not main.html. Main html has a fake scorm API to allow you to test your course on a web server (not an LMS) without disabling the scorm functionality, making for a smoother transition when you upload it.
As you have pointed out, this is only suitable for desktop and is intended as a convenience. If you need to test mobile devices, it is recommended that you do one of two things:
1. Upload the course to an LMS (ensuring the manifest is set up as described above - note this should be the default behaviour so you wouldn't usually need to change the reference).
2. Remove the spoor extension before you build, and test from a web server without having to worry about the LMS connection error message that spoor would give you otherwise.
I hope that helps.